Photo courtesy of Gulfstream Aerospace Gulfstream Areospace Corp.'s flagship G650 arrives in Geneva Saturday for the 2012 European Business Aviation Convention and Exhibition.

As a federal investigation into the crash of a Gulfstream G650 test aircraft moves into its final phase, a strongly worded letter has surfaced from the chairman of the National Transporation Safety Board in which she details agency concerns about Gulfstream’s role in the investigation.

The letter from NTSB chairman Deborah A. P. Hersman to Gulfstream president Larry Flynn is dated April 4, 2012, and is included in more than 2,000 pages of “factual findings” and other data released by the NTSB on its public docket over the course of the investigation.

The information on the docket, which includes Gulfstream’s assessment of what caused the tragedy, will be considered when the NTSB releases its final report on the probable cause of the accident, expected later this year.

The crash, which occurred April 2, 2011, in Roswell, N.M., during a takeoff run simulating late-stage failure of one of the aircraft’s two engines, resulted in the deaths of all four Gulfstream employees on board — experimental test pilots Kent Crenshaw and Vivan Ragusa and technical specialists David McCollum and Reece Ollenburg.

In the letter from Hersman to Flynn, she reiterates concerns she outlined during a March 22 meeting in her office in Washington, D.C.

“During the course of this investigation, NTSB investigators and management officials encountered a variety of situations that are not typical when dealing with parties to investigations,” Hersman wrote.

She went on to list:

• Gulfstream’s noncompliance with instructions from the NTSB investigator-in-charge relating to quarantine of accident-related telemetry data, informing Gulfstream employees about the nature and use of NTSB interviews and the prohibition on legal counsel becoming involved in the accident investigation;

• Unexplained missing evidence, including a computer hard drive containing accident-related telemetry data and flight test notebooks, both of which Gulfstream had been asked to safeguard because they were of significant interest and value to the investigation;

• Gulfstream’s withholding of relevant information relating to the existence and results of its internal safety audit;

• Gulfstream’s delay in providing requested factual information relating to the accident and in making staff available for participation in group activities, such as interviews and wreckage review; and

• General conduct and dilatory tactics prejudicial to the investigation, including multiple and excessive redaction requests, delays in providing comments on draft factual reports, combative and argumentative behavior on the part of Gulfstream’s legal counsel during witness interviews, excessive objections to disclosure of factual information based on claims of protection for proprietary data, excessive requests for repeat reviews of draft factual reports and a last-minute request for photograph copyright privileges.

“In sum,” Hersman wrote, “we expect all party participants to follow our rules and regulations and to act in good faith with a spirit of cooperation, rather than obstruction.”

Gulfstream responds

Gulfstream is prohibited from publicly discussing Hersman’s complaints while the NTSB’s final report is pending. However Flynn responded to issues brought up at the March 22 face-to-face meeting in a letter to Hersman dated March 30 — five days before Hersman’s letter outlining her concerns — and placed that response on the agency’s public docket.

“I believe it would be useful to provide you with some of the facts and circumstances surrounding … matters you raised at our meeting in order to give you a fuller understanding of Gulfstream’s role supporting the investigation,” Flynn wrote.

Among the things he listed:

• The flight data recorder, the cockpit voice recorder and all other onboard recording devices remained on the aircraft until removed by the NTSB.

• Upon the arrival of the NTSB’s investigator-in-charge at the accident site, Gulfstream promptly advised the investigator of telemetry data captured on a hard drive in a trailer at the airport as part of routine test activities. The company provided NTSB with an electronic copy of the data and dispatched a team of experts from Gulfstream to Roswell to instruct investigators in utilizing and accessing data.

• Upon learning the telemetry hard drive — which had been returned to Savannah — was missing, Flynn said, Gulfstream promptly notified the NTSB, the Savannah office of the FBI and retained the services of Global Resource Center, a security firm, to assist in the investigation.

When the FBI concluded the hard drive had not been stolen “but rather had likely been inadvertently discarded in the trash by the employee charged with its safekeeping, Gulfstream terminated (the) employee.”

While Gulfstream retained a group of experts to conduct a review of safety practices and culture in the company’s test and flight operations, at no time did it seek to delay NTSB activities as a result of the review, Flynn said.

“Gulfstream has responded to each and every request for information from the NTSB as promptly as possible,” he said. “In addition, Gulfstream has proactively provided a substantial amount of additional information that might assist the NTSB.

“I trust the above information helps confirm that Gulfstream has fully supported the NTSB investigation, has behaved with the highest ethical standards and has at all times made the safety of its flight test and flight operations its highest priority,” Flynn concluded.

In a submission dated May 21 and placed on the NTSB public docket last week, Gulfstream indicated the company “accepts full responsibility for the accident.”

“Developmental flight test is inherently risky, but risks can and should be appropriately mitigated,” the report stated.

Among the factors Gulfstream listed as likely leading to the crash were an overestimation of the angle at which the aircraft could safely lift off and a takeoff speed schedule that was not properly developed or verified, resulting in an unachievable test point for the accident run.

“Gulfstream’s internal analysis, review and approval processes did not identify those two errors prior to field performance flight testing,” the report stated, adding that “two prior wing drop events in the G650 field performance program and other flight test anomalies arising from these improper speed schedules were not widely reviewed or properly understood.”

The NTSB has not yet determined a probable cause for the accident.

Process versus product

While the NTSB’s public docket contains a massive amount of information, its website cautions that the data are raw and do not represent any conclusive determination.

After all of the tests and analysis are done, the NTSB staff will prepare a draft final report. The final deliberations will take place in a public meeting and then an abstract of the report will be published on the NTSB website, which will include the board’s conclusions, probable cause and safety recommendations. The final report will follow a few weeks later.

Although that report may be months away, most insiders are betting the crash had more to do with the process than the plane itself.

“It doesn’t matter who you are — Gulfstream, Bombardier, Airbus,” said a former test pilot familiar with business aviation. “When you are developing a new product, the pressure to get it certified in a timely manner is huge.”

That Gulfstream cited a breakdown in its internal analysis, review and approval processes indicated the crash was most likely a result of human error rather than any structural issues with the aircraft, he said.

It’s also important to remember that tests such as the ones the Gulfstream crew was performing the day of the fatal crash are part of the risks associated with the development of a new airplane, Chris Dancy, spokesman for the Aircraft Owners and Pilots Association, said at the time.

“In order to achieve FAA certification, flight-test crews have to determine the safe operating parameters of the aircraft,” Dancy said. “They have to be able to answer questions like ‘what happens if you lose an engine during takeoff.’

“With every new aircraft, the performance envelope has to be defined, and qualified flight-test crews then fly to the edge of that envelope.”

ABOUT THE CRASH

The crash of the Gulfstream G650 occurred as it was undergoing rigorous flight testing required for certification by the Federal Aviation Administration. The aircraft was practicing a takeoff with the simulated failure of one of its two engines – necessary to establish takeoff distance requirements under such an emergency. Testing was conducted at the Roswell International Air Center in New Mexico, which has a very long runway – 13,000 feet – and a lot of open airspace, which makes it ideal for test flights.

The crash of the Gulfstream G650 occurred as it was undergoing rigorous flight testing required for certification by the Federal Aviation Administration. The aircraft was practicing a takeoff with the simulated failure of one of its two engines – necessary to establish takeoff distance requirements under such an emergency. Testing was conducted at the Roswell International Air Center in New Mexico, which has a very long runway — 13,000 feet — and a lot of open airspace, which makes it ideal for test flights.